Check out example codes for "how to add a tooltip on a link in html". It will help you in understanding the concepts better.

Code Example 1

<style>
/* Tooltip container */
.tooltip {
  position: relative;

    
display: inline-block;
  border-bottom: 1px dotted 
black; /* If you want dots under the hoverable text */
}

/* Tooltip text 
*/
.tooltip .tooltiptext {
  visibility: hidden;
  width: 120px;

    
background-color: black;
  color: #fff;
  text-align: center;

    padding: 5px 0;
  
border-radius: 6px;
 
  
/* Position the tooltip text - see examples below! */
  position: absolute;

    z-index: 1;
}

/* Show 
the tooltip text when you mouse over the tooltip container */
.tooltip:hover 
.tooltiptext {
  visibility: visible;
}
</style>

<div class="tooltip">Hover 
over me

  <span class="tooltiptext">Tooltip 
text</span>
</div>

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